XMM newton has carried out pointed observations of the x RAY sky for more than a decade. The XMM newton serendipitous source catalog is ultimately intended to be the definitive catalog of x RAY…

This contract was awarded by the National Aeronautics and Space Administration (NASA) Shared Services Center to the University System of New Hampshire (UNH), through its University of New Hampshire division operating as the Office of Sponsored Research, to conduct research and analysis on X-ray sources detected by the XMM-Newton space observatory. The $277,766.85 grant-funded contract supports expanding on a previous project to systematically classify a large sample of 23,000 high-quality X-ray sources from the XMM-Newton Serendipitous Source Catalog. The work includes identifying rare and scientifically valuable objects, such as intermediate-mass black holes and tidal disruption events, for further in-depth study. This contract is not associated with a set-aside program. As the University System of New Hampshire's research and education capabilities position it well to support NASA's astrophysics research mission, this award builds on UNH's prior experience working on XMM-Newton data analysis.

XMM newton has carried out pointed observations of the x RAY sky for more than a decade. The XMM newton serendipitous source catalog is ultimately intended to be the definitive catalog of x RAY sources that IT detected. The newly released version 3XMM DR5 is 60 larger than its predecessor 2XMMI DR3 and contains 565,962 detections, corresponding to about 396,910 unique sources, from the first thirteen years of observations. IT is the largest x RAY source catalog ever produced. Therefore IT is a treasure for exploring the variety of the x RAY source populations and identifying rare important source types. We recently studied 4330 sources of the highest quality in the 2XMMI DR3 catalog in order to investigate the properties of different classes of x RAY sources and to search for rare important objects. Based on various properties of identified sources with known nature, we came up with a new source classification scheme to classify the rest of the sources whose nature is unknown. The quality of the classification was ensured with significant manual inspection, allowing US to identify many special objects of significant science value but poorly studied in the literature. We have devoted a series of papers to report the detailed properties of some of these special objects. With our extensive experience and considering the large amount of new sources included in the 3XMM DR5 catalog we propose to significantly expand the source sample to include 23,000 point sources that have s n 15 in at least one detection in the new catalog. We will apply our new classification scheme to systematically classify them. A large amount of manual inspection will be devoted to ensure the production of a large sample of x RAY sources with reliable classification and identification, which will be a very valuable resource to the astronomical community. All the rare important objects discovered, either from our new sample or from our previous project but not fully explored, will be elaborated on in detail. Especially, we propose to search for and have in depth studies of two special classes of objects. The first class is hyper luminous above 10 41 ERG s off nuclear x RAY sources, which are among the best candidates for the long sought after wandering intermediate mass black holes. The other class is tidal disruption events, which provide a unique way to find and study otherwise dormant supermassive black holes. They are also very valuable for understanding the accretion onto massive black holes in response to fast changes in the accretion rate. Our proposed work includes study of a few newly discovered objects that showed super eddington accretion signatures unseen before.